Capsule summary: the Revueltosaurus case
Fri Feb 29 18:59:10 GMT 2008
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In 1989,
Hunt named Revueltosaurus callenderi
based
on isolated teeth, and tentatively classified it as an
ornithischian dinosaur.
Hunt and Lucas (1994:234-235)
subsequently redescribed this animal,
referring it firmly to Ornithischia.
Hunt and Lucas (1989:91)
and
Hunt (2001:141-142)
mentioned a crocodilian (an early crocodile relative)
from the type locality of Revueltosaurus, but did not
describe it, name it or refer it to any existing taxon. This
specimen was described in
Hunt's (1994)
unpublished Ph.D dissertation, but considered distinct from
Revueltosaurus.
Heckert (2002)
again redescribed
Revueltosaurus, affirming its ornithischian identity.
Between 1994 and 2004, Lucas and his colleagues published several
more papers referring to Revueltosaurus as an ornithischian
(e.g.
Heckert and Lucas 1998,
Hunt et al. 1998:519,
Heckert 2001:283).
In March 2004, Bill Parker discovered new skeletons of
Revueltosaurus callenderi -- much more complete material
than the holotype. This discovery showed that
Revueltosaurus was not a dinosaur -- a fact first alluded to
in a published SVP abstract
(Stocker et al. 2004).
With further work, Parker and colleagues determined that
Revueltosaurus was a basal crocodilian.
In late 2004, Parker and his colleagues prepared a
manucript on this find: it was submitted to the Proceedings of the
Royal Society in October, resubmitted after review on December 2,
and
accepted on 10 December 2004.
Parker did not
conceal his findings from other palaeontologists, and so in late
2004,
Heckert (2004)
published a revised version of his
dissertation as a NMMNHS Bulletin and noted on p. 21 a personal
communication from Parker and colleagues that Revueltosaurus
was a non-dinosaurian archosaur.
If Hunt and colleagues had at this point discovered independently that
Revueltosaurus was not a dinosaur, it would seem logical that
their close colleague Heckert would have cited a personal
communication from them rather than Parker.
In March 2005, Parker gave
a talk on his findings at a conference in St. George, Utah
(Parker et al. 2005a:19).
Hunt and Lucas were in the audience, and afterwards
told Parker that they agreed with his reassessment but did not
otherwise comment.
In April of that year,
Hunt and Lucas (2005:53)
published an
abstract which stated that, through preparation of the skeleton
first mentioned by Hunt and Lucas in 1989, they had determined that
Revueltosaurus was a crocodilian rather than a dinosaur.
They did not cite Parker's reassessment.
In May 2005,
Parker et al. (2005b)
was published in the Proceedings of the Royal Society.
In autumn 2005,
Hunt et al. (2005)
published a paper in an NMMNHS Bulletin volume edited by Heckert
and Lucas, describing the postcranial skeleton of
Revueltosaurus. Although they cited Parker et al. (2005a,
2005b), they used their own abstract as the primary authority for
this discovery rather than Parker et al.'s abstract (which has
priority) or Parker et al's Proceedings paper (which
redescribed the material more comprehensively); and the
absence of citation of Parker's work in the Discussion and
Conclusions implied that their discovery was independent of
Parker's.
(Note. While preparing their 2005 manuscript in 2004,
Parker and his colleagues saw the New Mexico crocodilian first
mentioned by Hunt and Lucas (1989), and recognised it as a specimen
of Revueltosaurus. They refrained from including it in
their 2005 paper out of courtesy to Hunt, as it had been mentioned
in his dissertation.)
References
-
Heckert, Andrew B. 2001. The microvertebrate record of the Upper
Triassic (Carnian) lower Chinle Group, southwestern U.S.A. and the
early evolution of dinosaurs. Unpublished PhD Dissertation,
University of New Mexico, Albuquerque, 465 pp.
-
Heckert, Andrew B. 2002. A revision of the Upper Triassic
ornithischian dinosaur Revueltosaurus, with a description
of a new species. pp. 253-266 in Andrew B. Heckert and Spencer
G. Lucas (eds.), Upper Triassic Stratigraphy and Paleontology,
NMMNHS Bulletin 21.
-
Heckert, Andrew B. 2004. Late Triassic microvertebrates from the
lower Chinle Group (Otischalkian-Adamanian: Carnian), southwestern
U.S.A. NMMNHS Bulletin 27, 170 pp.
-
Heckert, Andrew B., and Spencer G. Lucas. 1998 [imprint 1997].
First use of ornithichian dinosaurs for biostratigraphic zonation
of the Upper Triassic. Albertiana 20:58-63.
-
Hunt, Adrian P. 1989. A new ?ornithischian dinosaur from the
Bull Canyon Formation (Upper Triassic) of east-central New Mexico.
pp. 355-358 in Spencer G. Lucas and Adrian P. Hunt (eds.), Dawn of
the Age of Dinosaurs in the American Southwest. New Mexico Museum
of Natural History, Albuquerque.
-
Hunt, Adrian P. 1994. Vertebrate paleontology and
biostratigraphy of the Bull Canyon Formation (Chinle Group, Upper
Triassic), east-central New Mexico with revisions of the families
Metoposauridae (Amphibia: Temnospondyli) and Parasuchidae
(Reptilia:Archosauria). Unpublished PhD Dissertation, University
of New Mexico, Albuquerque, 404 pp.
-
Hunt, Adrian P. 2001. The vertebrate fauna, biostratigraphy, and
biochronology of the type Revueltian land-vertebrate-faunachron,
Bull Canyon Formation (Upper Triassic), east central New
Mexico. pp. 123-151 in Spencer G. Lucas and Dana Ulmer-Scholle
(eds.), Geology of Llano Estacado, New Mexico Geological Society
Guidebook 52.
-
Hunt, Adrian P., and Spencer G. Lucas. 1989. Late Triassic
vertebrate localities in New Mexico. pp. 72-101 in Spencer
G. Lucas and Adrian P. Hunt (eds.), Dawn of the Age of Dinosaurs
in the American Southwest. New Mexico Museum of Natural History,
Albuquerque.
-
Hunt, Adrian P., and Spencer G. Lucas. 1994. Ornithischian
dinosaurs from the Upper Triassic of the United States.
pp. 227-241 in N. C. Fraser and Hans-Dieter Sues (eds.), In the
Shadow of the Dinosaurs: Early Mesozoic Tetrapods. Cambridge
University Press, New York.
-
Hunt, Adrian P., Spencer G. Lucas, Andrew B. Heckert, Robert
M. Sullivan and Martin G. Lockley. 1998. Late Triassic dinosaurs
from the western United States. Geobios 31:511-531.
-
Hunt, Adrian P., and Spencer G. Lucas. 2005. The postcranial
skeleton of Revueltosaurus callenderi (Archosauria:
Crurotarsi) from the Upper Triassic Bull Canyon Formation of
east-central New Mexico. New Mexico Geology 27(2):12.
-
Hunt, Adrian P., Spencer G. Lucas and Justin A. Spielmann. 2005.
The postcranial skeleton of Revueltosaurus callenderi
(Archosauria: Crurotarsi) from the Upper Triassic of Arizona and
New Mexico, USA. pp. 67-76 in Andrew B. Heckert and Spencer
G. Lucas (eds.) Vertebrate Paleontology in Arizona, NMMNHS
Bulletin 29.
-
Parker, William G., Randall B. Irmis, Sterling J. Nesbitt, Jeffrey
W. Martz and Lori S. Browne. 2005a. New material of
Revueltosaurus callenderi and its implications for the
identification of early ornithischian dinosaurs. p. 19 anon.
(eds.), Tracking dinosaur origins: the Triassic/Jurassic
terrestrial transition, abstracts volume. Dixie State College,
St. George, Utah, March 14-16, 2005.
-
Parker, William G., Randall B. Irmis, Stirling J. Nesbitt, Jeffrey
W. Martz and Lori S. Browne. 2005b. The Late Triassic
pseudosuchian Revueltosaurus callenderi and its
implications for the diversity of early ornithischian dinosaurs.
Proceedings of the Royal Society, Series B 272:963-969.
-
Stocker, M., William G. Parker, Randall B. Irmis and J. Shuman.
2004. New discoveries from the Upper Triassic Chinle Formation as
the result of the ongoing paleontological inventory of Petrified
Forest National Park, Arizona. Journal of Vertebrate
Palaeontology 24(3 suppl.):118A.
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